Half Tank, Half Chimp -- All Robot

It moves like a tank over rough terrain, but has four limbs with which to stand and use human tools. It is CHIMP, Carnegie Mellon University's (CMU) simian-inspired entry in the DARPA Robotics Challenge, which seeks to demonstrate a robot that can assist in dangerous disaster zones, by driving vehicles and wielding tools designed for humans.

Graphics: CMU Tartan Rescue Team

Tartan Rescue Team's CHIMP, or CMU Highly Intelligent Mobile Platform, is one of seven selected for Track A of the Robotics Challenge (CMU also has a team in software-only Track B). You can see the seven initial designs here. While some of the teams are developing humanoid robots, CMU's design is a bit different, a human-size robot that moves using tracks on the ends of its four limbs.

CHIMP's normal mode of locomotion is like a tank, with the tracks of all four limbs on the ground. This offers an advantage over debris and rough terrain, says CMU. CHIMP can also move on just two treads, when it needs to use its other two limbs to open a valve or operate power tools. Each limb ends in a manipulator that can grasp objects with "near-human strength and dexterity". When necessary, the operator can control individual joints to adapt the robot's motion to particular circumstances or extricate it from tight spots, says CMU.

While five of the seven Track A contestants are working on dynamically stable humanoid robots able to walk, CHIMP is statically stable and won’t fall down even if there is a computer glitch or power failure, says CMU. Dynamic balance makes a human nimble, but greatly increases the complexity, computational requirements and energy consumption of a robot. CMU says the team's focus on simplicity and dependability led it to tracked locomotion.

A goal of the Challenge is to demonstrate "supervised autonomy", which avoids the complexity of having to develop a fully autonomous robot. A remote human operator will give high-level commands controlling the robot’s path and actions, while its onboard intelligence will prevent collisions, maintain stability and keep it from harm, says CMU.

CHIMP will be pre-programmed to execute tasks such as grasping a tool, stepping on a ladder rung or turning a steering wheel without step-by-step direction from the human controller, circumventing the lag between command and execution. “Humans provide high-level control, while the robot provides low-level reflexes and self-protective behaviors,” says Tony Stentz, Tartan Rescue Team leader.